1. Field of the Invention
This invention relates to a method of manufacturing a chip component such as a chip resistor, and to an apparatus for manufacturing a unit element for use in the manufacture of the chip component, and to a structure for mounting the chip component manufactured by the method as mentioned above onto a substrate or the like.
2. Description of the Prior Art
A cylindrical chip resistor is known as a typical chip component applicable to a chip component feeding apparatus for feeding one by one in a predetermined orientation a multiplicity of chip components accommodated in bulk.
This chip resistor has a cylindrical ceramic unit element, a resistance conductor formed over the entire surface of the unit element, an armor covering the center of the resistance conductor and a pair of electrode conductors covering the ends of the resistance conductor. The resistance conductor is trimmed with grooves to control the resistance value, if necessary.
This known chip resistor is no need to orient its obverse and reverse side when it is fed by the apparatus, because its having no obverse and reverse side. But it is liable to roll because of its cylindrical shape, resulting in an unstable mounting onto the substrate or the like and hence in defectiveness such as a positional offset. This inconvenience applies to other similarly shaped chip components than the chip resistor.
It is a first object of the present invention to provide a new and improved method of manufacturing a chip component ensuring a stable mounting onto a substrate or the like and capable of being applied into a chip component feeding apparatus for feeding one by one in a predetermined orientation chip components accommodated in bulk.
A second object of the present invention is to provide a new and improved unit element manufacturing apparatus capable of efficiently manufacturing a unit element for use in the manufacture of the chip component described in the first object.
A third object of the present invention is to provide a new and improved chip component mounting structure ensuring a satisfactory connection of the chip component associated with the first object onto a substrate or the like.
In order to achieve the first object, according to a first aspect of the present invention, a method of manufacturing a chip component is provided. The method comprises the steps of burning an unburned unit element made of ceramic having prism-shaped parts at its ends; polishing edges of the burned unit element; and forming on the polished unit element a circuit conductor, an electrode conductor and an armor.
In order to achieve the second object, according to a second aspect of the present invention, an apparatus for manufacturing a unit element for a chip component is provided. The apparatus comprises a chuck for holding a prism-shaped base element in a predetermined orientation to rotate the base element around its central axis or an axis parallel thereto; a chuck wheel for translating the rotational axis of the chuck parallely along a predetermined arc trajectory; and a grinding tool turning at a position adjoining the arc trajectory to grind the center of the base element which is translated parallely in rotation along the arc trajectory.
In order to achieve the third object, according to a third aspect of the present invention, a chip component mounting structure is provided. The structure in which a chip component exposes to the exterior an electrode conductor and an armor which are contiguous to each other, and in which the electrode conductor is connected to a substrate electrode by a bonding material such as solder, wherein at the boundary between the electrode conductor and the armor, there is provided a gap at which the armor is inwardly hollowed to expose the surface of the electrode conductor to the exterior, so that upon the connection of the component, the bonding material can reach the gap and adhere to the exposed surface of the electrode conductor at the gap.
These and other related objects, aspects, features and advantages of the present invention will become apparent from the following detailed description in conjunction with the accompanying drawings.